This invention relates generally to human/computer interfaces, and more particularly to human/computer interfaces with force feedback that can operate over a network.
The Internet has, of late, become extremely popular. The origins of the Internet date back several decades to a U.S. government sponsored military/research/business wide area network (WAN) that was designed to remain operational even in the event of the catastrophe, e.g. a major earthquake or a nuclear war. To accomplish this goal, robust protocols and systems were developed which allowed a geographically distributed collection of computer systems to be connected as a WAN such that the loss of a particular computer, or group of computers, would not preclude the continued communication among the remaining computers.
While the use of the Internet has been prevalent for many years now, its use has been limited by the arcane and difficult commands required to access the various computers on the network. To address this problem, a protocol known as the "World Wide Web" or "WWW" was developed to provide an easier and more user-friendly interface for the Internet. With the World Wide Web, an entity having a domain name creates a "web page" or "page" which can provide information and, to a limited degree, some interactivity.
A computer user can "browse", i.e. navigate around, the WWW by utilizing a suitable web browser and a network gateway (e.g., an Internet Service Provider (ISP)). For example, UUNET, America Online, and Global Village all provide Internet access. Currently, the most popular web browser, known as the Netscape.RTM. Navigator.RTM., is made by Netscape Corporation of Mountain View, Calif. The web browser allows a user to specify or search for a web page on the WWW, and then retrieves and displays web pages on the user's computer screen.
The Internet is based upon a transmission protocol known as "Transmission Control Protocol/Internet Protocol" (or "TCP/IP" for short), which sends "packets" of data between a host machine, e.g. a server computer on the Internet, and a client machine, e.g. a user's personal computer connected to the Internet. The WWW is an Internet interface protocol which is supported by the same TCP/IP transmission protocol. Intranets are private networks based upon Internet standards, and have become quite common for managing information and communications within an organization. Intranets, since they adhere to Internet standards, can often use the same web browser software and web server software as are used on the Internet.
A web page typically includes static images and text. The images and text are specified in a "HyperText Mark-up Language" ("HTML") file that is sent from the web server to the client machine. This HTML file is parsed by the web browser in order to display the text and images on the display of the client machine. Other standardized languages or protocols are also being developed for use with the Internet and the World Wide Web. For example, the Virtual Reality Modeling Language (VRML) is used to provide visual virtual 3-D environments and allow one or many users to navigate through and interact as "avatars" in such an environment using a client computer system.
The Internet and the WWW also permit sound data to be transmitted over the Internet. For example, references to sound files can be embedded in HTML pages and can be played by the web browser. Data "packets" coded in TCP/IP format can also be sent from one client machine to another over the Internet to transmit sound data. This last-mentioned technique forms the basis for Internet telephony.
While the transmission of visual images (both static and dynamic, i.e. video), text, and sound over the Internet is well-known, the transmission of other types of sensory data has not been well explored. In particular, the transmission of data over the Internet pertaining to the sense of touch and/or force has not been established. "Force feedback" allows a user to experience or "feel" tactile sensations as provided through computational information. Using computer-controlled actuators and sensors on a force feedback device, a variety of realistic sensations can be modeled and experienced by the user. This useful and highly immersive sensory modality for interacting with the Internet has hereto been unavailable.